Overweight and obesity in the United States: prevalence and trends, 1960-1994.
OBJECTIVE
To describe the prevalence of, and trends in, overweight and obesity in the US population using standardized international definitions.


METHODS
Successive cross-sectional nationally representative surveys, including the National Health Examination Survey (NHES I; 1960-62) and the National Health and Nutrition Examination Surveys (NHANES I: 1971-1974; NHANES II: 1976-1980; NHANES III: 1988-94). Body mass index (BMI:kg/m2) was calculated from measured weight and height. Overweight and obesity were defined as follows: Overweight (BMI > or = 25.0); pre-obese (BMI 25.0-29.9), class I obesity (BMI 30.0-34.9), class II obesity (BMI 35.0-39.9), and class III obesity (BMI > or = 40.0).


RESULTS
For men and women aged 20-74 y, the age-adjusted prevalence of BMI 25.0-29.9 showed little or no increase over time (NHES I: 30.5%, NHANES I: 32.0%, NHANES II: 31.5% and NHANES III: 32.0%) but the prevalence of obesity (BMI > or = 30.0) showed a large increase between NHANES II and NHANES III (NHES I: 12.8%; NHANES I, 14.1%; NHANES II, 14.5% and NHANES III, 22.5%). Trends were generally similar for all age, gender and race-ethnic groups. The crude prevalence of overweight and obesity (BMI >> 25.0) for age > or = 20 y was 59.4% for men, 50.7% for women and 54.9% overall. The prevalence of class III obesity (BMI > or = 40.0) exceeded 10% for non-Hispanic black women aged 40-59 y.


CONCLUSIONS
Between 1976-80 and 1988-94, the prevalence of obesity (BMI > or= 30.0) increased markedly in the US. These findings are in agreement with trends seen elsewhere in the world. Use of standardized definitions facilitates international comparisons.
Flegal
K M
KM
National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville MD 20782, USA.
Carroll
M D
MD
Kuczmarski
R J
RJ
Johnson
C L
CL
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D009765:Obesity / Q000145:classification / Q000453:epidemiology*; D015995:Prevalence; D017678:Sex Distribution; D013997:Time Factors; D014481:United States / Q000453:epidemiology